Because I'm too lazy this morning, I didn't feel like reading 30 posts, but Have you ever done a compression check on this engine? If not, might be a good idea and if you do one could you post the readings for us to see?
You probably see where I'm going here and we're going back to the basics which never hurt as you already know.

 

Did read the other posts and did not see any compression check.
A couple of things kinda stick in my mind and they are;
you set the float level a little lower and that could affect power under load, also those brass insert tubes in the carb, I kinda remember them being removable and if the holes in them are plugged it would definitely affect the anti siphoning circuit .
You never answered my question of where you were taking the float height reading.
As you know there can be a big difference if the reading is taken at the toe or heel of the float. The specs for that were usually listed in the rebuild kit , were they?
Also different carb #s had different float level settings, were you able to make sure you used the right specs?

 

Ill take your advice greasemark and leave jetting where it is.I may swap out power valve and will look into ignition again.All ignition parts are new plugs,wires,cap and rotor are all i changed though.Firing order is correct.Dont know what else i could change in distributor.Is there something else i should check or replace?Im assuming its all solid state electronics and it either works or it doesnt.Yes hanky i did use manifold vacuum at a port in the back of intake and realized right away there are other problems.
Im sure this motor is old and getting tired and im only going to get it to run so good.I think im real close to leaving well enough alone,getting it through the winter and going through motor next spring.I have alot more time than money in the truck and being that it is in really nice condition its worth rebuilding the motor and fixing it up cosmetically little by little.

 

You know this truck better than I.
The fact that it may have some years on it doesn't mean it's had it.
I would still run a compression test and then you would have a much better idea of where you stand. Those old buggies held up much better and took abuse much better than today's stuff. Whatever you decide to do, wish you well !

 

Float specs were in with carb bit and im about a light 1/8 inch lower than specs.Under a load it has great acceleration.When i saw vacuum reading i knew a compression check was next.Ill have to borrow a friends tester at work tomorrow.I havent had to do alot of indepth trouble shooting in many years and got rid of alot of my testing equiptment.I know better now.Ill check inside distributor for anything that doesnt look right,corrosion etc and do compression test.Ive been driving it around the lat 2 days and its starting fine hot or cold and goes really good off idle and accelerates real good with the exception of that bit of hesitation at cruise speed.I think im down to looking for obvious things i may have overlooked instead of throwing more parts at it.The good old once over is always the best.

 

I did a compression test today and all cylinders were between 125 and 130 with the exception of one at 122,most are at 130.I went over everything one piece at a time.I ended up swapping power valves.I swapped out the new one from the carb kit for the old used one from the lincoln carb.It instantly cured all my problems.Idles smooth,no hesitation at cruise speed and has 17 inches of vacuum.Thankyou hanky and greasemark for all your help.I cant thank you guys enough.I hope all this helps someone out down the road.